Last Updated: Apr 10, 2021
SteroidCycle.org is intended for informational purposes only and does not take the place of professional medical advice.

Nandrolone Phenylpropionate (NPP) is a testosterone derived anabolic androgenic steroid. NPP is a 19-nor steroid due to a modification of one atom. Compared with dihydrotestosterone, NPP has less androgenic activity while having more anabolic activity than unmodified testosterone.

Nandrolone Phenylpropionate (NPP) Cycle
Nandrolone Phenylpropionate (NPP) Cycle

NPP was originally developed to treat osteoporosis and breast cancer in women but thanks to its powerful anabolic effects and relatively weaker androgenic effects compared with many other steroids, it is a popular choice for bodybuilders and performance athletes who wish to avoid dealing with more severe estrogenic and other side effects.

Author’s Note: The following guide is based on my personal experience and does NOT promote the illegal use of steroids (PEDs). I am currently using this supplement stack.

What is Nandrolone Phenylpropionate (NPP)?

Nandrolone Phenylpropionate, known as NPP for short, is a form of Nandrolone with the phenylpropionate ester attached. Another well known form of this steroid compound is Nandrolone Decanoate, also known as Deca-Durabolin. While NPP also used to be called Durabolin in the past, these days that name is avoided to prevent confusion between the two forms.

Nandrolone Phenylpropionate Structure
Nandrolone Phenylpropionate Structure

The Nandrolone hormone compound is exactly the same in both forms, it is simply the ester which gives each a slightly different property in the body; especially when it comes to half life and how fast it works, and how long it stays active in the bloodstream. This in turn dictates how often you’ll need to take your dosages.

NPP has a shorter half life and so requires more frequent injections to keep your levels stable compared with Nandrolone Decanoate.

Author’s Note: For real, NO-BS information on cycling steroids be sure to check out Straight From the Underground (my recommended underground steroid handbook). Everything in this book is based on first hand experience, not theory.

Meanwhile, if you are looking for something effective but don’t want to use steroids, here is my list of supplements that will help you with your quest in building muscles and getting leaner.

NPP Benefits (NPP Effects)

Nandrolone is well known for its many positive benefits and effects when used for performance enhancement purposes. You’ll also find that this compound comes with some excellent therapeutic effects as well, making NPP a quality all round steroid that will suit a range of users and goals.

Here are the main benefits and effects that you can expect with NPP:

  • Mass building – NPP is an excellent mass builder and many guys will include this steroid in every bulking cycle. Putting on quality muscle at a steady pace is a highly desirable benefit of NPP. This is not a compound that works super fast to help you gain mass quickly, but if you’re after both high quality and high quantity muscle gains, then NPP delivers.
  • Recovery – NPP has excellent therapeutic benefits for the joints in particular, and this is going to provide a significant boost to your recovery process. Expect to recover faster and be able to hit the gym for your next workout sooner, with greatly reduced muscle and joint soreness.
  • Lean muscle preservation – NPP has superb metabolic properties and this will make it more efficient for you to maintain lean gains during the off season. Additionally, if used in a cutting cycle then NPP helps conserve your muscle mass while you work on losing fat. Again, this is thanks to the high metabolic properties of Nandrolone. While NPP is not commonly used as a cutting steroid as often as it’s used for bulking, it can provide a highly beneficial role in a cutting cycle for any user who understands its functions and benefits.
  • Strength – Some users may see some increase in strength, however NPP is not particularly known for its ability to significantly boost strength to a noticeable level. When stacking with NPP with other steroids, it is likely to be other compounds that take care of your strength boost as this is not an area that Nandrolone excels in.

Nandrolone can be used for bulking or mass building, cutting, as well as for general athletic purposes. This makes it a highly diverse steroid that is often stacked with other compounds where it can contribute to more specific goals.

NPP Dosage and Cycle Length

Your dosage of NPP will depend on whether you’re using it mainly for therapeutic purposes, or for performance enhancement. When using this steroid to gain benefit from its therapeutic effects only, males can dose at 100mg to 200mg weekly and see substantial benefit including greatly improved recovery and joint relief.

For guys using NPP for bodybuilding a dosage of up to 400mg weekly is ideal. This strikes the right balance between reaping the benefits while keeping the side effect risk to a minimum. Those who are less concerned about side effects might consider increasing the dosage a little beyond 400mg but for most male users this will be the sweet spot that will deliver excellent results.

NPP is not an extremely fast acting steroid so cycle length should provide enough time to really see the benefits that this highly effect compound can deliver. Up to 12 weeks is recommended. The frequency of injections should be three per week, where the weekly dose is split evenly between injections. A three weekly injection routine ensures that blood levels of this steroid are evenly maintained throughout the cycle.

Females can make use of NPP but must be aware of the risks of virilization, and for that reason the female dosage should not exceed 50mg weekly for no longer than a 6 week cycle.

NPP vs Deca-Durabolin

The well known and very popular steroid Deca-Durabolin is also a Nandrolone steroid. It is the same as the Nandrolone steroid in NPP, but simply makes use of a different ester. While the ester used in NPP is Phenylpropionate, Deca-Durabolin is the brand name of Nandrolone decanoate. An ester attaches to the Nandrolone hormone and controls the way the hormone is released in the body once it has been injected.

By understanding different esters and how they work, it’s possible to create a steroid stack that contains compounds that use the same or similar esters, and this can make it easier to plan your post cycle therapy afterwards. At other times, you might want to combine short and long esters for different purposes. With Nandrolone available in these two ester types, you have the option to pick the one that best suits your plans and goals.

The hormone itself does not change once the ester detaches. NPP itself used to be known by the brand name Durabolin, giving us another indication of just how similar these two products are.

So what are the real world differences between NPP and Deca-Durabolin and which is the better choice for your goals?

With both compounds you get all the same benefits of Nandrolone which means excellent joint relief and therapeutic effects, improved recovery, excellent steady mass gains, greatly increased anabolic function and a lower level of androgenic effects compared with other steroid hormones.

The half life of NPP and Deca-Durabolin differ remarkably and that is the main difference to consider between the two. Nandrolone Decanoate has a very long half life of 6 to 8 days. This means it takes a day or two to even start circulating in the body enough to get its effects, and it will remain in the bloodstream for well over a week.

This shorter ester of Nandrolone requires much less frequent injections but also requires a longer cycle because of how long it takes for the effects to become active and beneficial. A Nandrolone Decanoate will normally be run for up to 16 weeks to gain maximum benefits of this slow acting form of Nandrolone.

Nandrolone Phenylpropionate has a much shorter elimination half life of about 3 days, so you’ll need to inject this compound much more often to maintain optimal blood levels. It is usually injected three times per week.

Both types of Nandrolone contain exactly the same active hormone, but if you’re after a faster acting form then NPP is the best choice. If you plan to do a longer cycle and want to inject Nandrolone less often, Nandrolone decanoate may be the best choice for you.

NPP Results

NPP delivers wide ranging results that will significantly boost performance and outcomes for all different types of athletes.

Your results will not only depend upon the effects of NPP, but just as much on the quality of your workouts during your cycle, your diet and just as importantly: what you do after the cycle to maintain your gains.

Here are the main results and advantages you can expect to see when using NPP:

  • Reduced stress hormones – by reducing cortisol stress hormones, muscle gains are more easily made and maintained and there is less tendency to gain fat. Stress hormones can rise with intense exercise, so NPP will work to reduce these hormones and keep your body in an anabolic state.
  • Increased nitrogen retention – a drop in nitrogen puts the body at risk of catabolism where muscle is lost. Balancing nitrogen is vital for maintaining an anabolic state, while negative nitrogen causes muscle tissue to be destroyed. NPP boosts nitrogen retention effectively, making this one of the most powerful aspects of this steroid.
  • Raise red blood cell count – improved endurance of the muscle with extra red blood cells transporting oxygen allows you to work out harder and longer, speeding up your results.
  • Boost protein synthesis – one of the most important effects of NPP is its boost to the synthesis or protein which provides the muscular building blocks. This speeds up muscle gains much more rapidly than if steroids are not being used.
  • Improved recovery – with increased red blood cells carrying more oxygen, the muscles can recover faster. Joints and muscle have a reduced tendency for soreness with Nandrolone’s therapeutic effects including a boost to collagen synthesis.

NPP has excellent benefits and effects for both bodybuilders and performance athletes. Athletes will value the recovery and therapeutic boost, while the seasoned bodybuilder will include NPP to gain the all round benefits of enhanced recovery, muscle preservation and mass gains.

Side Effects from NPP Cycle

Every steroid will come with its own side effect profile risks, but experienced steroid users will be familiar with most of the potential side effects that can experience with NPP. Some of these are certain to occur because of the nature of using steroid hormones, while other side effects can be determined more by individual reactions.

Some guys will experience more severe side effects than others, but it’s important to be aware of everything that you could be dealing with so you’re prepared to combat the side effects and focus on the positive benefits of NPP. This steroid can be considered one of the more mild when it comes to side effects, however there’s no escaping some negative effects.

Here are the main side effects to expect when using NPP for performance enhancement:

  • Androgenic side effects: These effects are milder with NPP compared with many other steroids. This category of side effects includes acne and baldness, but only males who are predisposed to these conditions are likely to experience them and for most men, it will be relatively mild. Female users should be alert for signs of virilization like hair growth and deepening of the voice.
  • Estrogenic side effects: Nandrolone is an aromatizing hormone so estrogenic effects can come about when testosterone is converted to estrogen, although they are normally not as severe as with many other steroids. These include development of gynecomastia, water retention and associated increase in blood pressure. Users should be able to easily control these effects by using an aromatase inhibitor.
  • Testosterone suppression: As with all steroids, NPP is going to suppress your natural testosterone production and this effect is very strong when using this compound. For many guys it will only take one dose for most or even all your testosterone production to shut down. This can’t be avoided but must be mitigated by combining NPP in a cycle with a testosterone compound so you don’t lose the vital bodily functions that this critical hormone provides. Following your NPP cycle you’ll need to implement post cycle therapy to speed up the stimulation of normal testosterone function again.
  • Cholesterol: Some users will experience a reduction in levels of good cholesterol (HDL) when using NPP. This effect can often be amplified through the combined use of an aromatase inhibitor, which many users are likely to be also be taking to control estrogenic effects. Those with existing cardiovascular complications or high cholesterol should closely monitor cholesterol levels throughout, and all NPP users should incorporate a good amount of cardio work into workouts while maintaining a diet high in omega-3 fatty acids.
  • Liver toxicity: NPP is not known to be hepatotoxic in users who use the steroid sensibly and with suitable breaks in between cycles. However all anabolic steroids can come with some risks to the liver, particularly when used at high doses or for prolonged periods of time. One study found that use of nandrolone in rats caused negative effects on lipid profile and liver enzymes.

Most male users of Nandrolone Phenylpropionate should be able to prevent or control the side effects well, and it’s more mild side effect profile makes it an appealing steroid to use for new users or those wishing to avoid the much more severe side effects that can be seen with some other compounds.

Female users may find that low doses of NPP bring about no or very little side effects, but this should be closely watched and when any signs of virilization begin the steroid should be stopped right away.

NPP PCT

NPP will suppress your normal testosterone function considerably, so post cycle therapy is critical after doing a cycle that includes NPP – whether it is being stacked with any other compounds or not.

PCT ensures you get your testosterone back on track after the steroids have suppressed production by providing the body with an external source of this critical hormone.

This also relates directly to your results: testosterone is vital for maintaining muscle mass and avoid fat gain. Post cycle therapy therefore can be considered as important as the cycle itself, and any missteps in your PCT can make your entire steroid cycle a waste of time if you aren’t going to maintain the gains you’ve made.

The timing of the start of your PCT will not only depend on NPP itself but on any other compounds being used in the cycle and their half lives and suppressive effects. If you don’t do any PCT, testosterone levels will take a significant amount of time to get back to normal levels and during that time, severe symptoms of low testosterone will happen as well as rising estrogen levels.

This makes post cycle therapy critical as the halting of exogenous testosterone during your steroid cycle stops, leaving the body with little or no hormone production.

Most NPP users will start PCT anywhere from three to 12 days after the final injection of the cycle. It is recommended to start earlier rather than later to avoid the onset of any symptoms of low testosterone like fatigue, loss of libido, depression, weight gain and muscle loss.

A combination of the Clomid and Nolvadex (Tamoxifen) is the most commonly used and most effective PCT strategy. Using these drugs for 4 weeks will get your testosterone working as it normally should. Dosages will differ depending upon your individual steroid cycle and level of testosterone suppression, and most users will start at a higher dose then decrease it for the second half of the PCT cycle.

Here is an example PCT cycle to follow after an NPP cycle:

  • Week 1: Clomid 50mg, Nolvadex 40mg
  • Week 2: Clomid 50mg, Nolvadex 40mg
  • Week 3: Clomid 25mg, Nolvadex 20mg
  • Week 4: Clomid 25mg, Nolvadex 20mg

To ensure gains are maintained to the maximum level, training should continue at a relatively high intensity right through your PCT cycle even if endurance and strength isn’t going to be felt at the same level as when you’re on steroids.

Common Q&A Related to NPP

Is Deca and Nandrolone the same?

Nandrolone comes in different forms, or esters. Some of these are sold under the brand name Deca, or Deca-Durabolin. It is important to look at the chemical name when choosing a steroid rather than just the brand name so you know exactly what you’re getting.

What are the side effects of Nandrolone?

Nandrolone and NPP can come with many of the same side effects that we see with most steroids, although it can be considered one of the more mild options that helps you avoid the more drastic side effects of some other compounds. Possible side effects include estrogenic developments such as gynecomastia and water retention, mild androgenic effects like acne, and heavy suppression of testosterone. This steroid can also reduce levels of good cholesterol (HDL).

Does Nandrolone cause hair loss?

NPP has some mild androgenic effects when compared to other more powerful steroids. Some men who are especially susceptible through genetics for male pattern baldness might see some of this issue develop, but it is not likely to be a problem for most male users of this steroid.

Is Nandrolone good for joints?

Yes, one of the greatest benefits of this steroids is its healing and therapeutic effects including bone and cartilage strengthening and soothing of joint pain. Some athletes make use of Nandrolone purely for this purpose only.

Does Nandrolone raise blood pressure?

Increased blood pressure is a side effect that can come about when water retention is not controlled when using steroids. Nandrolone can cause these estrogenic effects, but users should be easily able to control water retention or bloating through the use of an aromatase inhibitor, and this in turn will help prevent an increase in blood pressure.

My Conclusion and Recommendation

NPP is a versatile steroid that is useful for building mass, cutting and for athletic therapeutic purposes particularly to enhance recovery and minimize joint pain. Like all anabolic steroids used by bodybuilders and athletes, NPP is not legal to purchase.

Author’s Note: I am not advising anyone to use steroids. I’d either pick staying natural or using steroids. There is NO in between. If your idea is to do just few cycles and never touch steroids again, you better don’t even start.

Fortunately, for those of you who are looking for something effective but don’t want to use steroids, here is my list of supplements that I am currently using and feel work to improve your results! For those who follow me, you know I’d never steer you wrong.

If you enjoyed this guide and would like more real, NO-BS information on using steroids, then pick up Straight From the Underground (my recommended underground steroid handbook). Everything in this book is based on first hand experience, not theory.